Method of and apparatus for positioning strapping



April 23, 1968 P. LEMS 3,379,121

METHOD CF AND APPARATUS FOR POSITIONING STRAPPING Filed Feb. 15, 1967 4 SheetsSheet l INVENIUR. PETE R L E MS BY I April 23, 1968 P. LEMS 3,379,121

METHOD OF AND APPARATUS FOR POSITIONING STRAPPING Filed Feb. 13, 1967 4 Sheets-Sheet 2 STOP CAM PLATFORM CAMS C'U CID GATE CAM(FOR GATES. |,2,48x5) DELAYED GATE MOVEMENT STRAP SUPPORT CAM INVENTOR:

PETER LEMS By ikumcl 3W A ril 23, 1968 P. .LEMS 3,379,121

METHOD OF AND APPARATUS FOR POSITIONING STRAPPING Filed Feb. 15, 1967 4 Sheets-Sheer, 5

INVENTOR: PETER LE MS April 23, 1968 P. LEMS 3,379,121

METHOD OF AND APPARATUS FOR POSITIONING STRAPPING Filed Feb. 13, 1967 4 Sheets-Sheet 1 PB START BUTTON I C2 I 46 u w I GATE Cb CAM I 2 L gate g o -'I-\\ V2 gate 4 '9 ate 5 29 9 I l 44 I EAQLMQ Z gate 3 v l l l INVENTOR 1 9 PETER LEMS dw wel QsQpmM United States Patent 3,379,121 METHOD OF AND APPARATUS FOR POSITIONlNG STRAPPING Peter Lems, Wilmette, lll., assignor to Signode Corporation, Chicago, Ill., a corporation of Delaware Continuation-impart of application Ser. No. 495,931,

Oct. 14, 1965. This application Feb. 13, 1967, Ser.

11 Claims. (Cl. 100-2) ABSTRACT OF THE DISCLOSURE A strap positioning method and apparatus for encircling a hot rolling mill strip coil at a strapping station with a loop of steel strapping preparatory to tightening the loop about the coil. The loop is created by feeding the strapping endwise from a conventional strapping head through a fixed overhead chute centered above the strapping station until the ends of the loop overlap each other. Thereafter, the strapping head is lowered and, during the lowering operation, certain chute gates are successively opened to progressively release the loop of strap ing and allow the same to fall by gravity and become draped loosely about the coil and over a pair of strap supports which guide the loop to the proper strapping level during slack takeup and tensioning operations.

This application is a continuation-in-part of my prior United States patent application Ser. No. 495,931, filed on Oct. 14, 1965, and entitled Method of and Apparatus for Tightening and Strapping Involutely Wound Sheet Metal Coils, such application having matured into Patent No. 3,315,592 on Apr. 25, 1967.

The present invention relates to a method of and an apparatus for encircling an object with a loop of strapping material preparatory to tightening the loop about the object. More specifically, the method and apparatus of the present invention has been designed for use primarily in connection with the application of steel strapping to an involutely wound sheet metal coil at the strapping station of a strapping machine.

Heretofore, considerable difliculty has been encountered in the effective machine strapping of relatively massive strip coils which, as they issue successively from the rolling mill, are extremely hot and are therefore difficult to handle. In the first place, the fact that the coils arrive at the strapping station in a loose condition where the outermost few coil convolutions are not tight presents a problem in that it is necessary to tighten the coils before they can be efiectively strapped. Secondly, the feeding of a loop of strapping endwise about the coils at the strapping station is rendered difficult inasmuch as movement of the coils successively into and out of the strapping station requires a free passage that must not be obstructed by the strap-feeding chute or other strap-positioning instrumentalities which guide the strap to its position of circumvolution with respect to the coil.

One effective means for tightening a coil preparatory to tensionin g the strap loop about the same has been shown and described in my above-mentioned application. The present application being a continuation-in-part of such application, is directed to an effective means for encircling successive coils at the strapping station of a strapping machine with a loop of steel strapping material and in such a manner that no obstruction is presented to free passage of the coils into and out of strapping position at the strapping station.

In the past, where continuous strapping operations were performed on successive strip coils arriving at a strapping station, with or without coil tightening facilities, it has 3,379,121 Patented Apr. 23, 1968 ice been the practice to preform a loop of strapping material at a region removed from and centered above the actual strapping area by passing the strapping material endwise through a closed and generally circular chute, after which the chute, together with its contained loop of strapping material are lowered bodily into coil-encircling relationship at the strapping area. Coil strapping then takes place in the usual manner of strapping machine operation, the loop being forcibly pulled from the chute in centripetal fashion and tightened about the coil. Finally, in order to clear the path for removal of the strapped coil and arrival of a fresh unstrapped coil at the strapping station, it is necessary to raise the loop-forming chute bodily above the level of the coil to its original elevated position. It has also been proposed that, instead of shifting the entire chute vertically between its raised and its lowered position, only certain sections thereof be shifted, the movable sections being of sufiicient extent as to support the steel loop and cause the same to move bodily therewith. Because the strap forming chutes are of relatively large diameter, multiple and widely separated lifting devices are required to shift the chute or the individual sections thereof. Not only do problems of machine design arise, but additionally, in the case of sectional chutes, constant adjustment is required in order to maintain proper end-toend alignment of the various chute sections. These problems are further complicated if it is desired to employ automatic power-operated chute gates to release the strapping. Finally, the use of a vertically shiftable chute presents a hazard to both limb and property. Hot strip coils as they arrive at the strapping station are not always reasonably compact. Not infrequently a coil will arrive with a projecting loose terminal end which underlies the chute so that when the chute descends into the strapping area it engages this terminal end which, by reason of its rigidity and resistance to crushing, damages the chute beyond repair so that major replacement operations are required.

The present invention is designed to overcome the above-noted limitations that are attendant upon the use of vertically shiftable chute sections in the vicinity of the strapping station of a strapping machine and, toward this end, the invention contemplates the provision of a strap positioning apparatus which operates generally upon a lassoing principle to drop a performed loop of steel strapping by gravity over the upper end of the coil in coil-encircling relationship and to support and guide the loop during take-up operations to its proper horizontal level while the loop is being shrunk in centripetal fashion about the coil. In carrying out this procedure, briefly the invention contemplates the provision of a stationary strap-feeding chute which remains at a fixed elevated level appreciably above that of the coil, together with a series of power-actuated gates for releasing the strapping from the chute after the loop has been formed. A strapping head is movable bodily vertically between an elevated position wherein it is in operative register with the strap-feeding chute and a lowered position wherein it is disposed in operative strapping position at the strapping station. Control mechanism is provided for sequentially performing a series of operations including an initial feeding of the strapping endwise through the chute by the elevated strap-ping head, followed by a lowering of the strapping head. As the strapping head commences its downward movement, certain proximate chute gates become open to release the strapping while at the same time a remote or delayed action chute gate remains closed so as to hold the far reaches of the strapping loop captured in an elevated position. As the strapping head continues its downward movement, the sides of the strapping loop are maintained widely separated and, when the strapping head reaches an approximate mid-position in its downward travel, the remote gate becomes open to release the loop completely from the chute, at which time the loop will fall by gravity into encircling relationship with respect to the coil. To prevent the loop from falling to the floor and also to guide the loop into its proper horizontal strapping plane, a pair of retractable strap supports move to an advanced position against the side of the coil, and catch the falling loop, so to speak, thus determining the proper strapping level. These supports serve to slidingly guide the strapping material of the loop into contact with the coil while the strapping head assumes its lowermost position at the strapping level and commences its usual slack take-up operations. After all slack has been dissipated, the strapping head functions to tighten the coil convolutions by drawing certain excess portions of the strapping loop in a coil-tightening direction in accordance with the coil-tightening principles set forth in my copending application, above referred to, and, thereafter actual loop tensioning operations take place, followed by application of a seal to the overlapping ends of the loop and final severing of the thus tightened loop from the source of strapping. The coiltightening and other strapping machine functions, except insofar as they pertain to the initial positioning of the strapping loop about the coil, constitute no part of the present invention and no claim is made herein to any novelty associated with the same. Reference may be had to such application for a full understanding of these functions. The novelty of the present invention resides solely in the provision of a fixed elevated strap feeding chute from which the loop of strapping material is released in a particular manner so that it will come to rest in coil-encircling relationship and be guided into proper coil-engaging position during the actual strap tensioning operation by the strapping machine.

The provision of a strap positioning apparatus of the character briefly outlined above and possessing the stated advantages constitutes the principal object of the present invention. Other objects and advantages not at this time enumerated will become readily apparent as the nature of the invention is better understood.

In the accompanying four sheets of drawings forming a part of this specification, a preferred embodiment of the invention has been illustrated.

In these drawings:

FIG. 1 is a perspective view of a complete coil tightening and strapping installation embodying the present strap positioning apparatus and showing the same in approximately its midcycle of operation;

FIG. 1A is an enlarged sectional view taken on the horizontal plane indicated by the line 1A-1A of FIG. 1

and in the direction of the arrows;

FIG. 2 is a top plan view of the installation;

FIG. 3 is an enlarged sectional view taken transversely through one of several similar chute gates employed in connection with the invention, the section being taken on the line 33 of FIG. 2;

FIGS. 4 to 8 inclusive are similar side elevational views, entirely schematic in their representation, illustrating various sequential operations of the apparatus during the application of a strap to a coil;

FIG. 9 is a fragmentary combined pneumatic and electrical circuit diagram for the coil tightening and strapping installation of FIG. 1, but illustrating only the pneumatic and electrical circuitry associated with the strap positioning apparatus of the present invention, and

FIG. 10 is a fragmentary timing chart illustrating the cyclic operation of the strap positioning apparatus.

Referring now to the drawings in detail and in particular to FIGS. 1 and 2, there has been disclosed in these views a complete coil tightening and strapping installation embodying the present strap positioning apparatus. A coil which is to be tightened and strapped has been designated at C and it is shown as being positioned on a wheel-equipped pallet 10 at a strapping station 12 for cooperation with a vertically shiftable strapping machine 14 by means of which a loop of strapping material ST, established in accordance with the present invention, is tensioned about the coil, the overlapping ends of the loop united by application thereto of a seal, and the thus established band of strapping material severed from the source of strapping material.

Various commercial strapping machines having strapfeeding, strap-tensioning, seal-applying and strap-severing instrumentalities associated therewith are available for modification to accomplish the aims of the present invention but the particular machine selected for illustration herein is of the general type shown and described in my prior Patent No. 3,315,592, above referred to. The entire disclosure of such patent, insofar as it is consistent with the present disclosure, is hereby incorporated in and made a part of this application by reference thereto. In the present application, however, only such portions of the machine as are pertinent to the present invention are disclosed, together with the necessary modifications thereof.

The disclosure of FIG. 1 is representative of an actual experimental installation utilizing individual pallets such as that shown at 10 to bring successive coils C into position at the strapping station. It will be understood however that in a commercial installation successive coils C will be conducted to and from the strapping station 12 by means of a suitable intermittently operable conveyor, or on a series of live rolls as is customary in the art.

As previously stated, the strapping machine 14 is adapted not only to tension the loop of strapping S about the coil C but it also has facilities for drawing the loop of strapping in a coil tightening direction about the coil during strap tensioning so that when the loop is fully tightened all looseness in the coil will have been eliminated. For a full understanding of the manner in which such coil tightening operation takes place simultaneously with the tensioning of the loop, reference may be had to my prior patent above referred to.

Still referring to FIGS. 1 and 2, the strap positioning apparatus of the present invention involves in its general organization a superstructure 20 which overlies the strapping station and is maintained in its elevated position by means of supporting posts 22. The details of the superstructure 20 may vary for different installations but in the illustrated form this superstructure comprises a generally rectangular horizontally disposed frame which is made up of structural steel members including a relatively long side member 24, a relatively short side member 26, an end member 28 and a medial cross member 30. The strapping machine 14 is vertically slidable in a manner that will be made clear presently on a vertically disposed guide post 32. Disposed within the general horizontal plane of the superstructure 30 is a shelf-like support in the form of a web made up of individual plates 36 which collectively present a generally polygonal inner edge 38 (FIG. 3) which constitutes a strap guide for conducting the strapping material which is fed endwise from the strapping machine 14 in a closed path for the production of the elevated loop of strapping material ST which subsequently is to be applied to the coil C. This polygonal edge of the composite shelf 36 cooperates with a series of movable normally closed gates to provide what is commonly known in the art as a strap chute which has been designated in its entirety at 41 and through which the strapping material ST travels in endwise fashion during the creation of the loop. By reason of the five-sided polygonal nature of the edge 38, and of the fact that each gate 40 is substantially coextensive with a linearly straight portion of such edge, there is established a series of five chute sections, each of which has associated therewith an individual gate 40. The five gates have been individually labelled from one to five in FIG. 2 and in the circuit diagram of FIG. 9.

The various gates 40 are substantially identical in construction except for their linear chute spans and therefore a description of one of them will suffice for them all. As shown in FIG. 3, each gate is in the form of a length of channel stock which is pivotally connected by a pair of hinges 42 to the adjacent web plate 36 for swinging movement between closed and open positions shown in full and dotted lines respectively. In the closed position of the gate 40, the latter overhangs the edge 38 and the open side of the channel opposes this edge so as to confine the strapping material ST within the chute. In its open out-of-the-way position, the gate channel becomes raised and releases the strapping material so that the latter may fall downwardly under the influence of gravity for coil-encircling purposes in a manner that 'will be described in greater detail presently.

Movement of the gate 40 between its open and closed positions is effected under the control of a cylinder 44 which is hingedly connected as at 46 to the adjacent web plate 36 and which has asssociated therewith a plunger 48, the distal end of which is pivotally connected to an ear 50 provided on the gate channel. Means are provided for selectively supplying air to the opposite ends of the cylinder 44 under the influence of certain electrical and pneumatic circuitry which has been illustrated in detail in FIG. 9 and which will be fully described presently. It is deemed sufiicient for the present to state that the gates labelled one, two, four and five are adapted to be actuated in unison at an earlier point in the machine cycle than the gate labelled three, the latter gate being a delayed action gate.

As previously stated, the details of the strapping machine 14 have not been fully disclosed since they constitute no part of the present invention. It is deemed sufficient for purposes of description herein to state briefly that the machine is supported on a pair of guide rods (FIGS. 1 and 4 to 8 inclusive) which are slidable in guides 62 carried on a platform 64 which, in turn, is slidable vertically on the guide post 32. Vertical move ment is imparted to the platform 64 from a reversible pneumatic motor M2 (see also FIG. 9) through a power train of the chain-and-sprocket type and by means of which the strapping machine 14 may be shifted between its fully raised and its fully lowered position as shown in FIGS. 4 and 8 respectively. The strapping machine 14 is equipped with the usual strapping instrumentalities including reversible feed rollers for impelling the strapping S forwardly and endwise through a gate structure 68 (FIG. 1) and feeding the the same into the receiving end of the overhead chute assembly 41 when the machine is in its fully raised position, as well as for drawing the strapping rearwardly to tension the loop about the coil when the machine is in its operative lowered position. The machine is further provided with conventional seal-applying and strap-severing instrumentalities which become effective after the desired degree of tension has been attained in the strap loop.

In order to establish the desired strapping level for application of the loop of strapping ST to the coil C, a pair of identical pneumatically operable strap-supporting assemblies 70 are positioned on the supporting surface in the vicinity of the two adjacent corner posts 22. Each assembly has associated therewith a composite angular strap supporting arm proper 72 which is movable between a projected strap-supporting position wherein it is disposed substantially radially of the coil C with its forward end bearing against the cylindrical wall of the coil as shown in full lines in FIGS. 1 and 2, and a retracted position wherein it assumes an out-of-the-way position alongside the adjacent supporting post 22 as shown in dotted lines in FIG. 2. The extreme forward end of each arm 72 carries a coil-engaging roller 74 while the inner end thereof is pivoted on a stud 76 carried by a slide block 78 which travels in guideways 80 mounted on a base plate 82. The slide block is movable under the control of a cylinder and plunger assembly 83. At a region slightly removed from the pivoted end of the arm 72 there is provided a follower roller 84 which rides in a cam track 86. The track is so designed that when the slide block 78 assumes its forward position as shown in full lines in FIG. 2, the strap support arm 72 will project forwardly against the coil C in strap-supporting relationship to receive thereover the portion of the loop of strapping which falls thereon by gravity at the time the loop is released from the overhead chute 41. When the slide block 78 assumes its retracted position as shown in dotted lines, the follower roller 84 will move into a laterally turned portion 88 of the cam track 86, thus causing the strap support arm to swing to its retracted out-of-the-way position as previously described. In order to accommodate coils of varying height, means are provided for varying the effective level of the composite strap-supporting arms 72. To accomplish this, each arm is formed in two sections, the forward section being telescopically received within the rear section and secured in any desired extended position by means of a locking screw 90. Ordinarily a given coil C will have the strap loop applied thereto at a level midway between its ends and thus, to adjust the arms 72 of the two assemblies 70 for proper strapping of the coil, it is merely necessary to adjust the height of the forward arm section so that the horizontal portion thereof lies immediately below the horizontal mid-plane of the coil as illustrated in FIG. 1.

The strap positioning apparatus of the present invention is cyclic in its operation. The electrical and pneumatic operating instrumentalities associated with the apparatus are schematically illustrated in FIG. 9 and this view, when considered in conjunction with the timing chart of FIG. 10, will afford an understanding of the operation of the apparatus during a full machine cycle involving the tightening and strapping of a coil such as the coil C at the strapping station 12. Considering FIGS. 9 and 10 in conjunction with each other, the reversible platform-actuating motor M2 is operable under the control of a dual-solenoid valve V1 having windings W1 and w2 which are capable of selective energization by cams ClU and C1D respectively. The chute gates 40 laballed gate 1, gate 2, gate 4 and gate 5 are operable in unison under the control of a common solenoid valve V2 which, in turn, is operable under the control of a gate cam C2, the valve V2 serving to selectively supply air under pressure to the opposite ends of the various associated cylinders 44. The gate 48 labelled gate 3 is a delayed action gate and it is operable under the control of a solenoidactuated valve V3 which, in turn, is operable under the control of a pair of normally open contacts associated with a microswitch MS having an actuating finger 92 positioned in the path of a cam C3 suitably mounted on the machine-supporting platform 64. The microswitch MS is so disposed that its actuating finger 92 will be engaged by the cam 94 at a point in the apparatus cycle when the strapping machine 14 has reached approximately its mid-position during the downward travel thereof. The two strap-supporting assemblies 70 are operable under the control of a common solenoid-actuated valve V4 which, in turn, is actuated under the control of a strap support cam C4.

Considering now the cyclic operation of the apparatus in detail, and still referring to FIGS. 9 and 10, after a coil such as the coil C has been positioned at the strapping station 12, closure of the master switch MS and depression of the push button PB establishes a circuit for the electric motor M, the circuit extending from the source S, which may be an outlet leading from a commercial power line, and from the positive side of the line 11 through the lead 13, motor M, lead 15, push button PB, and lead 17 back to the negative side 19 of the line. Energization of the motor M serves to effect rotation of the various cams together with a stop cam CS which, upon initial rotation thereof, serves to close a pair of associated contacts to establish a bridging circuit across 7 the push button PB and maintain the motor M in operation until the end of the machine cycle.

It will be understood of course that the cyclic operation of the strap feeding mechanism of the present invention is preferably correlated with the cyclic operation of the strapping machine 14 and with the operation of any other functional auxiliary equipment associated with the coil strapping operation, as for example the intermittent movement of any conveyor which may be employed for transporting the coils C to and from the strapping station 12. Thus, the undesignated dotted line cam fragmentarily shown immediately below the strap support cam C4 may represent a control cam for a desired strapping machine operation such as a feed roll control cam or the like. Only such cams as are pertinent to the strap positioning apparatus of the present invention have been selected for specific description herein.

At the commencement of the apparatus cycle, the contacts which control the upward movement of the platform 60 are closed so as to establish a circuit through the winding w1 of the valve V1, thus energizing the reversible motor M2 in a direction tending to maintain the platform, and consequently the entire strapping machine 14, in its uppermost position as determined by the provision of a stop shoulder 100 on the guide post 32. This circuit for the winding W1 is designed generally by the reference numeral 21. At this time, the apparatus assumes the condition in which it is illustrated in FIG. 4.

During an initial portion of the apparatus cycle, and while the contacts associated with the cam C1U remain closed, various strapping machine operations take place while the strap positioning apparatus of the present invention is without function. Included in these operations is the feeding of strapping material endwise and sequentially through the various sections of the chute 41 so as to establish a closed loop of the strapping material, the loop being confined within the chute by reason of the fact that all of the gates 40 are, at this time, closed. At approximately 1l0 in the machine cycle, the contacts of the cam ClU become open while the contacts of the cam C1D become closed, thus establishing a circuit 23 through the winding w2 of the valve V1 and consequent reverse rotation of the motor M2 so as to cause the platform 60 to commence its descent. At the same time, the contacts associated with the cams C2 and C4 become closed, thus energizing the windings of the valves V2 and V4 by establishing circuits 25 and 27 respectively. Since the valve V2 is common to the cylinders 44 associated with the chute gates 40 labelled 1, 2, 4 and 5, these four gates immediately become open as the platform commences to descend. The gate labelled gate 3 however re mains closed and thus, as the strapping machine 14 descends toward the working area of the strapping station, the far reaches of the loop remote from the strapping machine 14 are retained by the closed gate labelled gate 3, while the remainder of the strapping of the loop is gradually pulled downwardly as indicated in FIG. 5. Energization of the winding of the valve V4 causes the cylinder and plunger assemblies 83 to project the strap supporting arms 72 forwardly against the coil C in the manner previously described.

At approximately 225 in the apparatus cycle, the cam C3 which is carried by the platform 64 engages the actuating finger 92 of the microswitch MS, thus closing the contacts thereof and causing energization of the winding of the valve V3 by means of a circuit 29. Actuation of the valve V3 causes the plunger 46 to be projected from the cylinder 44 associated with the gate 40 labelled gate 3, thus opening this latter gate and releasing the remote reaches of the loop of strapping. The loop is at this time freed entirely from the chute 41 and remains attached only to the strapping machine which continues to descend toward its operative strapping position. The loop thus falls to the position wherein it is illustrated in dotted lines in FIG. 6, with the strap draped, so to speak, over the two strap support arms 72 but completely encircling the coil C.

A vertically adjustable stop shoulder 102 movably tounted on the guide post 32 determines the operative strapping position or level for the strapping machine and, at such time as the platform engages this shoulder, further downward movement thereof ceases. The various control cams associated with the motor M continue to rotate, thus maintaining continuity of normal strapping machine operations including feed wheel reversal by means of which the looseness in the strapping loop is initially taken up, thus drawing the strapping machine inwardly toward the coil as illustrated in FIG. 7, the coil itself is tightened by drawing the strapping in a coil-tightening direction, and binding tension is applied to the loop.

At approximately 315 in the cycle, the contacts associated with the cam C4 become opened, thus deenergizing the winding of the solenoid actuated valve V4, and retracting the strap supporting arms 72 of the assemblies 70, thereby shifting these arms to their out-of-theway positions as previously described.

Continued cam rotation as relation to the strapping machine operations serves to complete the various strapping operations of which the strapping machine is capable such as the application of a seal to the overlapping ends of the strap loop and the final severing of the loop from the source of strapping, all in the manner disclosed in my copending application, Ser. No. 495,931, above referred to. However, at approximately 340 in the apparatus cycle the contacts associated with the cam C1D become open and the contacts associated with the cam ClU become closed, thus deenergizing the circuit 21 and energizing the circuit 23 so as to drive the pneumatic motor M2 in a direction to cause raising of the platform and the strapping machine 14 carried thereby. Such movement of the platform is illustrated in FIG. 8, the completely tightened and strapped coil being unobstructed so that it may readily be transported from the strapping station 12 without interference.

The strapping machine cycle, as well as the strap positioning apparatus cycle, is terminated by opening of the contacts associated with the stop cam CS and the consequent deenergization of the motor M. The completely tightened coil C, with the strap applied thereto, may then be removed from the strapping station 12 and both the strapping machine 14 and the strap positioning apparatus of the present invention will be in condition for the application of a strapping loop to the next succeeding coil C arriving at the strapping station.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be restored to without departing from the spirit of the invention. For example, while the present strap positioning apparatus has been shown and described herein as being associated with a strapping machine of the type disclosed in my Patent No. 3,315,592, above referred to, the apparatus is readily aplicable to other forms of strapping machines, whether the latter be provided with coil-tightening facilities as described in such application, with other types of coil tightening facilities, or with no coil-tightening means whatsoever. If desired, the control instrumentalities for the strap positioning apparatus may be completely divorced from any association with the control devices for the strapping machine operation so that the apparatus is operated independently of the strapping machine. Furthermore, the present strap positioning apparatus is not necessarily limited to the specific timer controlled operation described herein since it is within the purview of the invention to provide manual controls for effecting the desired platform moving, gate opening and strap supporting and guiding operations if desired. Therefore, only insofar as the invention has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, in combination, a curved strap chute fixedly disposed in an elevated position above the level of the strapping station and adapted to conduct strapping in a generally arcuate path to estab lish the loop, a strapping machine movably bodily between a lowered position wherein it is disposed at the strapping station and an elevated position wherein it is in operative register with said chute, said strap chute having proximate regions adjacent said strapping machine and a remote reach portion diametrically opposed to the strapping machine when the latter is in its elevated position, means effective when the strapping machine is in its elevated position for feeding strapping to the chute, said strapping machine during initial downward movement thereof serving to conduct the adjacent portions of the loop downwardly from the proximate regions of the chute, releasable strapping retaining means effective during such initial downward movement of the strapping machine to retain the strapping in the remote reach portion of the chute, means effective after a predetermined downward movement of the strapping machine for releasing said strapping retaining means to thus release the loop completely from the chute and allow the same to fall by gravity into the strapping station in object-encircling relationship, means effective when said strapping machine is in its lowermost position for tensioning the loop about the object, and reversible means for moving the strapping machine between its elevated and its lowered position.

2. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, the combination set forth in claim 1, wherein said strapping retaining means comprises a normally closed gate, and wherein said releasing means comprises a cam effective to open said gate.

3. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, the combination set set forth in claim 2, wherein said cam is mounted on and movable bodily with the strapping machine.

4. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, the combination set forth in claim 1, wherein said strapping retaining means comprises a normally closed fluid-actulated gate, and a reversible fluid device for actuating said gate, and wherein said releasing means comprises a directional valve operatively connected to the fluid device, and a cam effective to actuate said directional valve.

5. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, the combination set forth in claim 4, wherein said cam is mounted on and movable bodily with the strapping machine.

6. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, in combination, a strap chute fixedly disposed in an elevated position above the level of the strapping station and adapted to conduct strapping in a generally arcuate path to establish the loop, a strapping machine movable bodily between a lowered position wherein it is disposed at the strapping station and an elevated position wherein it is in operative register with said chute at a strap-feeding station, means effective when the strapping machine is in its elevated position at said strap-feeding station for feeding strapping to said chute, normally closed proximate gates in the vicinity of said strap-feeding station and on opposite sides of the latter for retaining the proximate region of the loop confined within the chute, a normally closed gate remote from said strapfeeding station for retaining the remote reach portion of the loop confined within the chute, reversible means for moving said strapping machine between its elevated and its lowered position, means effective upon initial downward movement of the strapping machine from said strap-feeding station for simultaneously opening said proximate gates to release the proximate regions of the loop, means effective after a predetermined downward movement of the strapping machine for opening said remote gate to thus release the loop completely from the chute and allow the same to fall by gravity into the strapping station in coilencircling relationship, and means effective when the strappin machine is in its lowered position for tensioning the loop about the coil at the strapping station.

7. In an apparatus for positioning a loop of strapping about an object disposed at a strapping station preparatory to tensioning the loop about the object, the combination set forth in claim 6 including, additionally, a reversible fluid-actuated device for actuating each of said gates, wherein the means for simultaneously opening said proximate gates includes a directional valve operatively connected in common to the reversible fluid-actuated devices associated with the proximate gates, and a cam effective to actuate said directional valve, and wherein the means for opening said remote gate includes an additional directional valve operatively connected to the reversible fluid-actuated device associated with the remote gate, and an additional cam effective to actuate said additional directional valve.

8. In an apparatus for positioning a loop of strapping about an object disposed at a straping station preparatory to tensioning the loop about the object, the combination set forth in claim 7, wherein said additional cam is mounted on and movable bodily with the strapping machine. r 9. The method of forming and positioning a loop of strapping about an object preparatory to tensioning the loop around the object which comprises: feeding strapping endwise into a substantially continuous fixed elevated chute disposed, at least in part, above the level of the object to establish the loop and thereafter causing the loop to be conmpletely released from the elevated chute and thus discharged in its entirely and solely by gravity downwardly below the level of the fixed elevated chute and into object-encircuing relationship against a strap supporting member for subsequent tensioning of the loop at a level below that of the elevated chute.

10. In an apparatus for forming a loop of strapping and positioning the loop about an article disposed at a strapping station preparatory to tensioning the loop about the article, a fixed substantially continuous elevated strap forming and supporting chute disposed, at least in part, above the level of the strapping station and adapted to conduct strapping in a generally arcuate path to establish an elevated loop of strapping, means for feeding strapping to the elevated chute to provide said elevated loop, and means effective after the loop has thus been established to release the loop campletely from the elevated chute and allow the same to fall solely by gravity below the elevated level of the chute and into the strapping station in articleencircling relationship.

11. In an apparatus for positioning and tensioning a loop of strapping about an object disposed at a strapping station, in combination, a fixed stubstantially continuous strap chute disposed in an elevated position above the level of the strapping station and adapted to conduct strapping in a generally arcuate path to establish said loop, a strapping machine movable bodily between a lowered position wherein it is disposed at the strapping station and out of register with the elevated chute and an elevated position wherein it is in register with the chute, means effective when the strapping machine is in its elevated position of register with the chute for feeding strapping to the chute, said strapping machine, during and by reason of its downward movement thereof, serving to initiate withdrawal and release of the loop from the chute and consequent dropping thereof solely under the influence of gravity into the strapping station in objectcncircling relationship, means disposed at said strapping station and engageable with the released strapping for limiting the extent of downward dropping movement of the latter to thus determine the strapping level, means effective when the strapping machine is in its lowered position for tensioning the loop about the object at said strapping level and means for moving the strapping machine between its elevated and its lowered position.

No references cited.

BILLY J. WILHITE. Primary Examiner. 

